When James K. Polk was elected president in 1844, the United States was locked in a diplomatic struggle with Britain over the rich lands of the Oregon Territory, while the territories that would later comprise California, Nevada, Utah, Arizona, New Mexico, and part of Colorado all belonged to a more powerful Mexico, which also threatened to take Texas. When Polk left office four years later, the country had acquired all these lands, becoming the continental United States we know today. Robert Merry chronicles Polk's fulfillment of manifest destiny through the era's powerful debates and towering figures, including outgoing President John Tyler and Polk's great mentor Andrew Jackson; his defeated Whig opponent Henry Clay; generals Zachary Taylor and Winfield Scott; Secretary of State James Buchanan (who would precede Lincoln as president); Senate giants Thomas Hart Benton and Lewis Cass; Daniel Webster and John C. Calhoun; and ex-president Martin Van Buren, who was, like Polk, a Jackson protégé but became a Polk rival.

"Filled with intricate stories of personal conflict, psychological gamesmanship, and unintended consequences.... One of the most astute and informative historical accounts yet written about national politics, and especially Washington politics, during the decisive 1840s."—NYTBR